This proposal requests support for the 1979 Rochester International Conference on Environmental Toxicity. The conferences have been convened annually since 1968 on various topics of toxic aspects of our environment. This year's conference concerns polluted acid rain. There exists a variety of atmospheric pollutants which condense in rain and snow. Acid production and pollution distribution have become problems. The problem of what can be done to control this type of pollution is very complicated because the source of the pollution is seldom the area where environmental perturbation occurs. The conference will focus on the scientific and inter-state aspects of this problem in an attempt to define current principles of rain acidification and pollution, the biological consequences of these processes, and the role that state, federal, and industrial agencies can play in affecting amelioration of the problem.